Equipment for the automatic aseptic inoculation and sampling of microbial cultures

Equipment has been designed and constructed for the automatic aseptic inoculation and sampling of microbial cultures. It enables fermentations to be started and samples to be taken round-the-clock, according to a predetermined program. The equipment is suitable for microbial processes on both a laboratory and a factory scale.     

QSAR modeling and transmission electron microscopy stereology of altered mitochondrial ultrastructure of white blood cells in patients diagnosed as schizophrenic and treated with antipsychotic drugs.

Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.     

Decontamination of food-packing material using moist heat

Depending on the microbiological quality, it may be necessary to reduce the number of microorganisms on the packing material before use with food products. Treatment with hydrogen peroxide at elevated temperatures is most commonly used. Residues of hydrogen peroxide, however, are undesirable. Systems not using chemicals obviously would be preferable. For products which do not allow the growth of bacteria, such as many acid products and products with a low water activity, often it is sufficient to inactivate moulds and yeasts. Moulds and yeasts can be inactivated by temperatures below 100°C provided the water activity is high enough. At low humidities at the same temperatures hardly any reduction in viable count is obtained. A prototype machine was built to investigate the inactivation of microorganisms on the surface of packing material, using moist heat for a short time, similar to the time needed for decontamination by peroxide. The number of viable dry spores of Penicillium roqueforti can be reduced by a factor of >1000 within 3 s at 90°C and 100% humidity. Moist heat decontamination is a promising method which could help manufacturers pack food in a microbiologically safe manner, without the use of chemicals. Further work is needed, however, to determine the inactivation of other relevant microorganisms. Received 09 September 1996/ Accepted in revised form 31 January 1997     

Safe biotechnology 9: values in risk assessment for the environmental application of microorganisms. The Safety in Biotechnology Working Party of the European Federation of Biotechnology.

Risk assessment for the deliberate release of microorganisms into the environment is traditionally carried out on a case-by-case basis. In a similar approach to that used when assessing human pathogenicity, we propose an alternative approach by introducing risk classes to facilitate or complement this type of risk assessment. These consider several sets of scenarios that address the different values that need to be protected. Examples of this approach include risk-class definitions for soil fertility and biodiversity.     

Safe biotechnology (4). Recommendations for safety levels for biotechnological operations with microorganisms that cause diseases in plants

The Working Party on Safety in Biotechnology of the European Federation of Biotechnology has proposed a classification of microorganisms that cause diseases in plants. In this paper appropriate safety levels are proposed for these classes of microorganisms in order to ensure that research, development and industrial fermentation work with plant pathogens will limit the risk of outbreaks of diseases in crops that could result from work with such microorganisms when they are cultivated in laboratories, glasshouses and biotechnology installations.Co-opted: J. Dähne, J. Drozd, M. Lemattre, I. M. Smith , E. M. A. WaterschootA Report prepared by the Working Party on Safety in Biotechnology of the European Federation of Biotechnology (EFB)

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RAPID SCREENING FOR SALMONELLA IN FISHMEAL BY ENRICHMENT-IMMUNOASSAY

We previously described an enrichment-immunoassay utilizing a T6 monoclonal antibody capture enzyme-linked immunosorbent assay. Here we evaluated it for the rapid screening for Salmonella in fishmeal obtained from the national Animal and Plant Quarantine service in the People's Republic of China. In this method, the number of Salmonella present is first expanded by appropriate enrichment cultures, and the pathogens are then directly detected by the T6 immunoassay. In a total of 94 enrichment cultures of fishmeal, we obtained an overall concordance of 98% between the results obtained in parallel by this method and by conventional test method. The positive prediction by this method was 92% and the negative prediction was 100%. The turn around time for the new test was 27 h which is a significant improvement from the turn around time exceeding 96 h required for the conventional test method. This test proved to be compatible with the routine work flow in the practical setting of a quarantine laboratory.